CN201294470Y - Phase control intelligent electricity-saving controller for three-phase asynchronous motor - Google Patents
Phase control intelligent electricity-saving controller for three-phase asynchronous motor Download PDFInfo
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- CN201294470Y CN201294470Y CNU200820178669XU CN200820178669U CN201294470Y CN 201294470 Y CN201294470 Y CN 201294470Y CN U200820178669X U CNU200820178669X U CN U200820178669XU CN 200820178669 U CN200820178669 U CN 200820178669U CN 201294470 Y CN201294470 Y CN 201294470Y
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Abstract
The utility model relates to a three-phase asynchronous motor phase-controlled intelligent energy-saving electrical controller relating to the field of a motor accessory, a traditional starting operation device is characterized in that the starting current and the operating torque moment thereof are difficult to correctly match with the loading, and the very high current peak can be generated during the switching moment, thereby the generated mechanical vibrating can damage a motor rotor, a shaft connector, a middle gear and the loading, thereby the controller adopts a low voltage fully-automatic phase-controlled intelligent energy-saving circuit, and a single chip control circuit, a voltage automatic detecting circuit, a current detecting circuit, a loading tracking circuit and a motor feedback power factor circuit are connected in an electricity saving circuit, which enables the motor to realize the optimum operation under the state of the low power consumption of the motor, and the controller has the beneficial effects that the starting current of the motor is low, the safety performance is high, and the damages to the loading are small.
Description
Technical field
This reality has novel the motor field of accessories that relates to, especially intelligent energy-saving controller.
Background technology
Three-phase AC asynchronous motor is with its low cost, the extensive use in every profession and trade of advantages such as high reliability and easy care.But, it is when across-the-line starting and operation, exist very big shortcoming: at first, its starting current is up to 5-7 times of rated current, this needs electrical network that very big allowance is arranged, and the useful life of having reduced electrical apparatus control equipment, increase maintenance cost, even influenced the normal operation of other electric equipment; Secondly, the operation torque can reach 3 times of normal torque, and this can produce load and impact, and increases the friction and the additional maintenance of drive disk assembly.
Traditional starting operation mode is as follows:
1.. in the motor stator sub-loop, seal in reactor, make a part of voltage drop on reactor;
2.. star-delta conversion decompression starting (Y-Δ).Be connected into star during electric motor starting, behind the proceed-to-send, become delta connection by a transducer;
3.. starting compensator starting (auto-transformer starting).
Traditional starting operation equipment volume is huge, changes distance apart from being difficult to control, that is to say to be difficult to obtain suitable starting current with moving with the motor commentaries on classics of load matched; And can produce very high current spike, consequent mechanical oscillation meeting infringement rotor, mandrel connector, idler gear and load switching moment.
Summary of the invention
The purpose of this utility model can overcome traditional starting operation shortcoming for providing a kind of, energy-conservation economize on electricity during operation, and the phased intelligent energy-saving controller of threephase asynchronous with overcurrent protection, overvoltage protection, open-phase protection function.
The technical scheme that realizes above-mentioned purpose is as follows:
The phased intelligent energy-saving controller of threephase asynchronous; the input of this controller and output insert the major loop of threephase asynchronous; input is through short switch; with phase demodulation road circuit; the constant current soft starting circuit; phase shortage and overload protecting circuit connect in succession; be connected with output at last; synchronizing signal sample circuit and squaring circuit; voltage detecting circuit; and described phase detector circuit connects in succession; described synchronizing signal sample circuit also with the load tracking circuit; the anti-overload protecting circuit of current detection circuit and described phase shortage connects; described synchronizing signal sample circuit also with the single-chip microcomputer control circuit; power amplification circuit connects in succession; power amplification circuit also respectively with described phase detector circuit; the constant current soft starting circuit; phase shortage and overload protecting circuit are connected with bistable flip-flop circuit; also have limit for tonnage bypass circuit one end to be connected with described phase detector circuit in addition, the other end is connected with described constant current soft starting circuit.
Each signal of telecommunication sample circuit is connected with major loop; wherein current sampling circuit connects by three instrument transformers; voltage sampling circuit connects by three synchrotrans; and through optical coupling isolator access control circuit; squaring circuit is connected with phase-comparison circuit; the load tracking circuit is connected with single chip machine controlling circuit with phase-comparison circuit respectively; high frequency signal generator and power amplification circuit; high-power letter integration module; major loop connects in succession; motor protecting circuit is connected with signal generator with current sampling circuit respectively, and the limit for tonnage bypass circuit is connected with the load tracking circuit; operation and fault display circuit are connected with power supply with the motor protecting circuit power amplification circuit respectively.
Has single chip machine controlling circuit in the such scheme, the sweet single-chip microcomputer of preferring of the core of this control circuit, control module, this module adopt charactron to show, press key control, whole starting process is all finished according to preestablishing automatically by single-chip microcomputer, so it is extremely convenient to operate.
The technical characteristic of scheme
1.. the voltage ramp starting characteristic
At first add a voltage U s to motor, voltage linear rises afterwards, is increased to maximum voltage Umax from Us.At this moment, the voltage that is added on the Terminal of motor equals the electrical network input voltage.The selectable voltage of Us is 80-300V.Ts is set by the user, and can select in second at 1-90.For example power of motor size, load size etc. are selected suitable parameters, reach the optimum start effect.The characteristics of this start mode are that starting is steady, can reduce the impact of starting current to electrical network, alleviate the mechanical oscillation that starting torque is brought load simultaneously greatly.The full voltage hard reboot often damages motor and equipment, phased power-saving technique device can detect the load of motor and offer power of electric motor, under the prerequisite that does not reduce staring torque, only offer desired power in the motor start-up process, and can set as required in the scope start-up time at 0 second-30 seconds, start-up course is level and smooth stepless, can reduce the starting current of motor effectively, its starting current only is 50% of a standard electromotor hard reboot electric current, the effective limit inrush currents of current limiting characteristic efficiently, avoid unnecessary impact moment and to the rush of current of distribution network, can effectively control the temperature rise of motor, prolong the life-span of motor greatly.
2.. voltage kick function
Load has very big stiction; In the voltage ramp start mode, voltage is ascending rising gradually.If directly working voltage slope mode is started, in a period of time of starting beginning,, do not overcome the stiction of load because of institute's making alive is too little, cause the situation of damaging motor because of heating.Voltage kick function has then solved this problem.Before electric motor starting, export a voltage U t earlier, and continue for some time Tt, in order to overcome stiction, treat to start according to original mode again, thereby protected motor better after the motor rotation.
3.. energy conservation characteristic
The electric energy that induction alternating current (AC) motor consumes usually particularly operates in underload state when it greater than the electric energy of its actual needs, and this unnecessary electric energy dissipates with the form of vibrations, heating, noise and ferromagnetic loss etc.The flexibility energy management pattern of phase control techniques is set up effective motor power monitoring control mode between distribution system and alternating current machine, running current, voltage and the power with motor is adjusted at optimum state in real time, realizes the purpose of energy-saving run.
4.. optimize operation characteristic
Provide the characteristic of power according to loading, efficient, productivity and the useful life that can effectively improve motor, save the energy and expense simultaneously.Can carry out extremely excellent control to single-phase and three-phase alternating-current motor, optimize security operating mode to satisfy.
5.. protective feature
Have three kinds of defencive functions: overcurrent protection, overtemperature protection, open-phase protection.If one of above-mentioned three kinds of faults, module is outage automatically in starting or running, and the demonstration failure cause of can glimmering of the charactron on the control box after waiting to fix a breakdown, can recover normal by reset key.Applicable to the application scenario that requires the comparison strictness, has the function that overcurrent and phase shortage are protected incision bypass operation automatically.
6.. subdue the economize on electricity of the degree of unbalance of three-phase voltage
Decomposite negative sequence component voltage U 2 from three-phase imbalance voltage by symmetrical component method, it is a counterclockwise preface amount, it can make motor produce the braking moment of additional opposite spin, if overcome it and keep former speed by positive direction, the positive sequence energy that will additionally increase with respect to one times of negative sequence component could keep former speed, if U2=1.5%U1, then to increase by 2 * 1.5% power, for zero-sequence component is exactly because the imbalance of voltage produces residual voltage or the current component that the skew of voltage center's point causes, so the utility model can be subdued the degree of unbalance voltage thereby can bring significant power-saving effect.
7.. reduce the running current economize on electricity
Impedance Z L when starting is minimum for motor, the electric motor starting electric current is generally (3.5～5.5) IA, perception light fixture starting current is generally (1.5～2.0) IA, after adding electricity-saving appliance, equal to insert the anti-resistance of the equivalence ZF of some, can will reduce starting current greatly, can reduce the running current of underload motor and perceptual light fixture simultaneously, if the motor of a lot of platforms or the load of team control motor are arranged, very big economize on electricity income are just arranged.
8.. suppress the economize on electricity of transition surge
Transition and surge are the distortion of a kind of instantaneous attitude of electric current and voltage on the simple alternating current wave circuit.Say that synoptically the electric cost that makes the user that fails to be convened for lack of a quorum in wink increases, simultaneously, the safe operation of the destruction equipment that fails to be convened for lack of a quorum in wink.Present technique can be subdued higher harmonic components, plays power savings to a certain degree.This is because present technique has adopted optimal magnetic material and special control technology to come the momentary variation of curtage steady.Du/dt is suppressed to make the voltage on the working line to be stablized, and this has played protective effect to a certain degree to power consumption equipment, makes power consumption equipment avoid the infringement of the surge voltage in the system.
The technical functionality that has is as follows:
1.. reduce the motor starting electric current (during general alternating current motor across-the-line starting, impulse current be rated current 5-7 doubly);
2.. supply line's generation transient voltage falls when avoiding motor starting, causes equipment, instrument misoperation;
3.. produce moment when preventing to start and impact, and make mechanical off-axis or produce waste product;
4.. starting motor (soft starter device generally allows 10 times/hour, and makes the motor unlikely overheated) more continually;
5.. can prevent water hammer effect to load of the pumps, prevent pipeline breaking;
6.. to some process application (as yarn dyeing machinery), can prevent that producing uneven dyeing owing to starting is too fast causes quality problems;
7.. to some frangible container grouting production line, can prevent the container breakage;
8.. need the control starting current, reduce impact, also can adapt to occasion (as injection molding machine) simultaneously than the low capacity supply transformer to machinery;
9.. can reduce the adaptive capacity of electrical network, save the expense of increasing capacity spending;
10.. digital intelligent control module structure, energy-saving run, be protected in one.Outstanding feature is that volume is little, function is strong, easy for installation, simple to operate, non-maintaining, reliability is high, is the desirable regeneration product of traditional starting equipment.
The utlity model has following beneficial effect:
1. the electricity consumption intelligent management function of " flexibility " is provided at power distribution network with between with electric loading;
2. possess perfect soft start and soft stop function, can guarantee that motor continuously smooth ground starts, mechanical shock and great start-up current that conventional Starting mode follows electric motor starting to produce have been eliminated, effectively reduce the wearing and tearing of bearing and belt, generally reduce the mechanical stress of chain and gear, thereby prolong the useful life of motor;
3. adopt the control of intelligentized microprocessor, real-time regulated, electric moter voltage is reduced to Minimum requirements and rotating speed keeps constant automatically under light load condition, therefore reduced needn't loss.If load increases, voltage will rise automatically to prevent motor stall
4. select the iron core main body of the very high ferrite iron core of magnetic capacity as inductor for use, improved the complete machine operating efficiency, oneself power consumption descends;
5. adopt heat dissipation design in unique cabinet, when the temperature inside the box reached 55 ℃, three high-speed fans carried out ventilation in the case, guarantee working properly.
Description of drawings:
Fig. 1 is the composition frame chart of the phased intelligent energy-saving controller of the utility model threephase asynchronous;
Fig. 2 is main circuit principle of compositionality figure;
Fig. 3 is one-chip computer module principle of compositionality figure
Embodiment
Now in conjunction with the accompanying drawings the technical solution of the utility model is described further.
Main circuit and phased circuit and single-chip microcomputer mutual encapsulation in same housing, simultaneously built-in a plurality of electric currents, voltage sensor.With connector module and control box are linked together, realize the setting and the demonstration of various functions.
Main circuit is 6 square direct current module chips of glassivation, by integrated solder technology, it is attached on the DBC (ceramic copper-clad plate), and welds together with conducting copper plate.When module was used, conducting copper plate closely contacted by heat-conducting silicone grease with fin.This structure makes module have very high insulation property and heat dispersion.
Phased power-saving technique phase-shift circuit partly is to be the SOP28 encapsulation, the power supply of 5V single power supply, and totally digitilized processing mode has very high phase shifting accuracy, symmetry.Control end is added the 0-10V level signal, i.e. may command phase shifting angle degree.
Synchrotrans output synchronizing signal is given phase-shift circuit, wherein one the tunnel gives single-chip microcomputer in addition, gathers the benchmark of voltage, current signal as single-chip microcomputer.Like this, change the error of calculation of bringing, improved computational accuracy if just overcome ac frequency.
Voltage sensor and current sensor.All used Hall element in two kinds of transducers, had the advantages that volume is little, reaction is fast, Linearity is high, placed inside modules easily by integrated design with modular structure.Two kinds of transducers are passed to 12 high-speed a/d converters with voltage analog, current analog amount, by the A/D conversion, the corresponding digital amount are passed to single-chip microcomputer, handle in order to single-chip microcomputer.Demonstration, control section adopt serial port and single-chip microcomputer to carry out communication, and this communication modes has significantly reduced the line of this part and inside modules.5 charactrons show, 8 by key control, make show with control directly perceived, convenient.
The utility model is to adopt latest integrated chip controls technology to cooperate motor phase sequence adjustment technology, constantly detects power of electric motor factor and operation power condition, the input voltage of real time altering motor and electric current.When detecting motor under the situation of zero load → underloading → fully loaded multiple load variations, keep the motor constant rotational speed constant, can monitor the phase angle a between motor voltage and the electric current automatically,, in several milliseconds of times, adjust phase angle a automatically according to the changing condition of load.High power switch element by special use, voltage current waveform is carried out " otch " control, adjusted the voltage of supplying with motor automatically, reduce the motor magnetic hysteresis loss, reduce the copper loss and the iron loss of motor, guarantee that the power output of motor and load in real time reach optimum Match.Improved the service efficiency of electric energy, having reached economizes on electricity falls the purpose of damage.
Phased power-saving technique adopts closed loop feedback system to be optimized control, voltage and current waveform by real-time measurement motor, because motor is an inductive load, there are a phase difference usually in its electric current and voltage waveform, and this phase place extent is relevant with the size of its load.Reach actual phase difference and compare, and control the rectifier bridge trigger angle according to this, in time adjust the power of input motor, realize motor " supply promptly required " so that the electric current and the voltage of optimization to be provided to motor according to the desired phase difference of motor characteristic.
Phase control techniques has adopted high power semi-conductor and integrated circuit (IC) chip Detection ﹠ Controling triggering system to realize the contactless intelligent controlled function; the high speed processing characteristic and the fast reaction characteristics of its detection and control integrated circuit chip; make phased power-saving technique device can handle the motor dynamic characteristic under the various operating modes automatically, have soft start, energy-conservation economize on electricity, optimize characteristics such as operation and protection.
Phase control techniques is different from traditional frequency converter power-saving technology in design fully, it has adopted the unique control technology of current/voltage vector sensing dynamic monitoring, do not change original all operation characteristics of motor, thereby avoided frequency converter because of turning down the drawback that speed causes production efficiency to descend, filled up the blank that frequency converter institute can not reach.
Claims (2)
1; the phased intelligent energy-saving controller of threephase asynchronous; it is characterized by the input of described controller and the major loop that output inserts threephase asynchronous; input is through short switch; with phase demodulation road circuit; the constant current soft starting circuit; phase shortage and overload protecting circuit connect in succession; be connected with output at last; synchronizing signal sample circuit and squaring circuit; voltage detecting circuit; and described phase detector circuit connects in succession; described synchronizing signal sample circuit also with the load tracking circuit; the anti-overload protecting circuit of current detection circuit and described phase shortage connects; described synchronizing signal sample circuit also with the single-chip microcomputer control circuit; power amplification circuit connects in succession; power amplification circuit also respectively with described phase detector circuit; the constant current soft starting circuit; phase shortage and overload protecting circuit are connected with bistable flip-flop circuit; also have limit for tonnage bypass circuit one end to be connected with described phase detector circuit in addition, the other end is connected with described constant current soft starting circuit.
2; the phased intelligent energy-saving controller of threephase asynchronous according to claim 1; it is characterized by each signal of telecommunication sample circuit is connected with major loop; wherein current sampling circuit connects by three instrument transformers; voltage sampling circuit connects by three synchrotrans; and through optical coupling isolator access control circuit; squaring circuit is connected with phase-comparison circuit; the load tracking circuit is connected with single chip machine controlling circuit with phase-comparison circuit respectively; high frequency signal generator and power amplification circuit; high-power letter integration module; major loop connects in succession; motor protecting circuit is connected with signal generator with current sampling circuit respectively, and the limit for tonnage bypass circuit is connected with the load tracking circuit; operation and fault display circuit are connected with power supply with the motor protecting circuit power amplification circuit respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200820178669XU CN201294470Y (en) | 2008-11-06 | 2008-11-06 | Phase control intelligent electricity-saving controller for three-phase asynchronous motor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200820178669XU CN201294470Y (en) | 2008-11-06 | 2008-11-06 | Phase control intelligent electricity-saving controller for three-phase asynchronous motor |
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| CN201294470Y true CN201294470Y (en) | 2009-08-19 |
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| CNU200820178669XU Expired - Fee Related CN201294470Y (en) | 2008-11-06 | 2008-11-06 | Phase control intelligent electricity-saving controller for three-phase asynchronous motor |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102097983A (en) * | 2011-02-12 | 2011-06-15 | 鞍山市权晟电子电力有限公司 | Network type all-digital motor soft starter |
| CN102570965A (en) * | 2012-02-24 | 2012-07-11 | 江苏煌明能源科技有限公司 | Program control energy-saving device of motor |
| CN102811016A (en) * | 2011-06-04 | 2012-12-05 | 深圳市万禧节能科技有限公司 | Intelligent motor power saver |
| CN102902259A (en) * | 2012-11-06 | 2013-01-30 | 河南恒天电子信息技术有限公司 | Internet of things-based multimode intelligent electricity-saving application system for motor |
| CN103048963A (en) * | 2012-12-14 | 2013-04-17 | 新疆希望电子有限公司 | Motor intelligent real-time monitoring and control system |
| CN104483535A (en) * | 2014-12-08 | 2015-04-01 | 河北汉光重工有限责任公司 | Starting voltage testing method for all-digital follow-up system |
| CN105553384A (en) * | 2016-01-26 | 2016-05-04 | 中山顺富节能科技有限公司 | Intelligent motor power saver |
| CN106849522A (en) * | 2015-12-03 | 2017-06-13 | 天津市银钻电机有限公司 | A kind of Intelligent motor control device |
| CN108599670A (en) * | 2018-05-07 | 2018-09-28 | 孟晓丽 | Speed regulation control method for special frequency converter for heavy-load motor |
| CN109067293A (en) * | 2018-10-17 | 2018-12-21 | 丁毅 | The electricity-saving appliance of monophase machine |
-
2008
- 2008-11-06 CN CNU200820178669XU patent/CN201294470Y/en not_active Expired - Fee Related
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102097983A (en) * | 2011-02-12 | 2011-06-15 | 鞍山市权晟电子电力有限公司 | Network type all-digital motor soft starter |
| CN102811016A (en) * | 2011-06-04 | 2012-12-05 | 深圳市万禧节能科技有限公司 | Intelligent motor power saver |
| CN102570965A (en) * | 2012-02-24 | 2012-07-11 | 江苏煌明能源科技有限公司 | Program control energy-saving device of motor |
| CN102570965B (en) * | 2012-02-24 | 2014-03-19 | 江苏煌明能源科技有限公司 | Program control energy-saving device of motor |
| CN102902259A (en) * | 2012-11-06 | 2013-01-30 | 河南恒天电子信息技术有限公司 | Internet of things-based multimode intelligent electricity-saving application system for motor |
| CN103048963A (en) * | 2012-12-14 | 2013-04-17 | 新疆希望电子有限公司 | Motor intelligent real-time monitoring and control system |
| CN104483535A (en) * | 2014-12-08 | 2015-04-01 | 河北汉光重工有限责任公司 | Starting voltage testing method for all-digital follow-up system |
| CN106849522A (en) * | 2015-12-03 | 2017-06-13 | 天津市银钻电机有限公司 | A kind of Intelligent motor control device |
| CN105553384A (en) * | 2016-01-26 | 2016-05-04 | 中山顺富节能科技有限公司 | Intelligent motor power saver |
| CN108599670A (en) * | 2018-05-07 | 2018-09-28 | 孟晓丽 | Speed regulation control method for special frequency converter for heavy-load motor |
| CN108599670B (en) * | 2018-05-07 | 2019-07-23 | 孟晓丽 | Speed regulation control method for special frequency converter for heavy-load motor |
| CN109067293A (en) * | 2018-10-17 | 2018-12-21 | 丁毅 | The electricity-saving appliance of monophase machine |
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20090819 Termination date: 20171106 |
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| CF01 | Termination of patent right due to non-payment of annual fee |